Lock



April 28, 1953 F. MGCONNELL LOCK Filed Jan. 6, 1948 2 SHEETS-SHEET 1 FIG.

INVENTOR. FRANK M CONNELL ATTORNEYS.

April 8, 1953 F. MGCONNELL 2,636,376

LOCK

Filed Jan. a, 1948 2 sms-Ts smE'r 2 FIG. 3.

FIG. I0.

g INVENTOR.

FRANK MCCQNNELL Patented Apr. 28, 1953 UNITED STATES PATENT OFF ICE.

to The American Hardware- Corporation, New. Britain, Conn, acorporation of. Connecticut Application January 6, 1948, Serial No. 676" 21 Claims.

My invention relates. to latching: devices and iniparticular. to. a latch for; applicationto a door or the like.

. It is an. object. of my invention to provide an improved device of. the character indicated.

It is another object to. provide an improved.

latch device for articular application torelative- 1y thin door sections.

It is a more specificobiect to provide. an improvedlatch unit adaptable. in. combination with alock toipermit a. flush-type finished mounting on a door,

Itis also an object to provide improved antipicking means for alatchi'ng devic of the char.- acter indicated.

It is still another object to provide an improved rosette structure for. use in combination with a,

latch.

It is a more. specific. object to provide a simple, relatively inexpensive, and. dependable structure to meet the above objects.

Other objects and various further feature of. the-invention will be pointed out or will occur to those skilled in the art from a reading of. the folelowing specification in conjunction with the accompanying drawings. In said drawings:

Fig. l isaside view, showing a combination according to the invention asapplied to a. door;

Fig. 2 is a view similar to Fig. l, but with the.

operationof certain elements of the latch unit of Figs. 3. 4, and-5 Fig. '7 is-a rear view of parts of the rosette. structure. shownin thecombination of Figs. land 2.; Fig. 8 is asectional view ofthe rosette, of Fig. '2', taken substantially in the. plane 8-43. of Fig- 7;

Fig. 9' is a fragmentary view of a part ofthe latch unit of Figs. 8, 4, and 5, shown with av slight modification for performing a difierent. function in thecombination such as shown in Figs. 1 and 2; Fig; 10 isa view similar to Fig; 9, for a different relationship of parts; and

Fig- I1. is a sectional vierrtaken: inthe' plane ii -iii. of.E-i&;.'5.

Brieflystated.v my" inyentioncontemplates an.

with certain parts.

2V. improved combination latch unit and rosette, whereby this combination may be applied to doors including those of relatively thin section. When so applied, this combination may also be utilized in conjunction with conventional locks. In short, my invention contemplates a maximum employment of unit-handling subassemblies requiring but a simple engagement with one another when assembled to a door; by unit-handling, I mean that each subassembly shall be a completely assembled functioning unit which shall require. nofurther parts or assembly operations to complete. its assembly. In a preferred. form, my novel rosette. structure may be unit-handling and incorporates means coupling two rotatable members, one of which may be linked as by a spindle to actuate the latch mechanism, and the other of which may be. associated with a lock, such as a cylinder lock, also unit-handling. In the form to be described, the rosette includes gears for positively associating. the two rotatable members, and these gears are secured in a unitary structure having a knob and dogging means, the rosette structure being suitable for application directly to a .face of a door. The latch unit, as it is shown and described, is unit-handling and generallycylindrical to fit within a, bore in the edge of. the. door, and by a novel employment of resilient members it may be utilized either as a dead bolt. or as a resiliently actuated latch; novel means are. also shown. whereby. the latch unit may be rendered pick-proof.

In assembling my lock unit, rosette unit, and latch unit to a door, the door need be bored sub stantially only with a transversely extending lockreceiving bore. offset froma latch-receiving bore in. the front edge of the door. These bores may be said to overlap in the sense that a plane including the axis of the latch bore and normal to the axis of the lock bore actually overlaps 01'' passes across the lock bore, so that in a relatively thin door a cylindrical lock in the lock bore may be said to overlap a cylindrical latch in the latch bore.

In Figs. 1 and 2*of the drawings, my invention is'shown as a combinationapplied to a door 32. The combination may include an outwardly facing cylinder lock 3!- and an inner knob is. for actuating a latch 33. The lock 3! may be flushmounted on the front face of the door 32 and j the; spindle 5h that iacarriedbythelock 3i en ages the rosette structure I! on the axis of the inner knob F3. The other rosette axis may be in actuating relation with the mechanism for actuating the latch may be housed in a case 18 of generally cylindrical form for insertion as a un t into a bore 19 (see the broken-awav portion of Fig. 2) in the ed e of the door H. The outer radius of the c lindrical latch case 18 preferably clears the lock 3 i. so that the spacing between the lock axis and the latch axis may be said to exceed the outer radius of the latch ca e I8; in other words. the spacin between rosette axes may be said to be at least the distance from the lo kactuating axis (i. e. axis of rotation of key to the side o the lock unit nearest the latch unit. plus the distance from t e latch-actuat ng a is (axis of s indle 3Q) to the si e of thelatch unit nearest the lock unit. The latch case if! may carry a latch front or face plate 20 to serve as a bracket for securing the asse bled latch mechanism in position on the door ll. Both'the lock 3! and the rosette st ucture I a be held securelv to the d or 32 bv a sin e s t of securin screws 35 passin through mountin ho es 2? (Fig 7) and engaging lu s 31 of the lock 3!.

In accordance with a feature of the invention, the inner knob l3 may be formed in a unitary structure with the rosette H, which, in addition to providing a means for operating a latch, may impart additional function: when used in combination with a latch such as the latch 33. In a preferred form. and with particular reference to Figs. 7 and 8, the rosette I! com rises two coupled rotary members 21-22, which may have meshing gear teeth. Both members 2i22 may be journalled in a rosette housing comprising an outer plate 23 and an inner plate 24. Dogging means such as a dog member 25 may be supported in a guide 26 for manual actuation, to slide into or out of dogging engagement with the teeth on rotary member 2!. The housing plates 232 1l may be provided with a plurality of holes 27 to receive mounting screws to secure the unit to the face of a door. To preserve a unit-handling relationship, however, one of the housing plates may be provided with lugs 28 which may be bent over the other housing member. Both rotary members 2!-22 preferably include boss parts 29-30 to be received in bearing apertures in the inner housing plate 24; both bosses 29-33 may include spindle-engaging means. A socket in the lower boss 38 may engage the roll-back or other actuating element of the latch mechanism 33, as by means of a transversely extending spindle; and the look spindle 35 may engage a corresponding socket in the upper boss 29.

With the described combination, it will be clear that the latch 33 may be actuated from the outside of the door by a turning of the lock key i5, and from the inside by actuation of knob hi, the inside actuation being effected through the gears on rotatable members 2 i-22; to permit latch actuation by knob I3 independently of lock 3!, I prefer that lock 3! may be of a type permitting sufiicient angular lost-motion between spindle 3-5 and lock 31. though the latch mechanism 331 may incorporate no dogging means, the dogging means 25 in the rosette assembly I! may be adequately effective in dogging the latch mechanism M from the inside of the door H. With a proper design, the spindle 35 may fail before failure of any of the rosette parts, should the dogging mechanism 25 be in position to dog the 1315011115. Thus the security aiforded by a doggedlatchlof the.de-

It will further be noted that even scribed combination may be unimpaired, even under circumstances in which the outer door lock 3! or the key 15 may be overstressed.

It will be appreciated that because the rosette structure i'i may accommodate two spindles on spaced axes, it is possible to apply a standard lock (such as the lock 3!) and a standard latch (such as the latch 33) in a completely flush mounting on a door 32 of a relatively thin section. The lock 3! may be accommodated in a transversely extending bore 38 in the door, and said bore 38 may be adequately spaced in non-interfering relation with the bore 19 into which the latch 33 is inserted. The coupling and dogging functions may be performed by the rosette I? in a relatively flat structure which cannot disturb the overall flush-type appearance of the finished combina- 'tion.

.. In accordance with a feature of the invention, the latch mechanism for the latch I4 of Fig. 1 or for the latch 33 of Fig. 2 may be of such construction as to provide alternative functions for either of the applications of Figs. 1 and 2. In the form illustrated in Figs. 3, 4, and 5, the latch function is one of normal resilient urging for an extended position of the latch bolt 39, while in Figs. 9 and 10 the same structure is shown in use as a dead bolt.

Referring to Figs. 3, 4, and 5, my novel latch structure is shown carried in a case it which may be of generally cylindrical shape. The case it may be formed of two generally semicylindrical case members illii held together at the back end by a cap i2 and at the front end by a sleeve member at, which may carry the face plate or latch front 28. Both cap 42 and sleeve 43 may lockingly engage the case members til-4i, as by bayonet or snap-action means 44-45.

The latch bolt 39 may carry a shank 46 having a head A? to engage a latch carriage, and the carriage may include spaced side members 4849 to be guided by the inner walls of the latch case l3. In the preferred form shown, resilient means such as a spring 50 acting between the plate 5! and the latch bolt 38 serves to urge the bolt 39 into an extended position, with the head 4'! in engagement with the latch carriage. The plate 5| may be fixedly retained in the case 18, as by beads 52 formed in the case i8.

In accordance with a feature of the invention, novel roll-back means are employed for actuating the latch 39 by way of the latch carriage. The roll-back means preferably comprises essentially two roll-hack elements 53-5 i mounted for rotation on spaced axes and preferably meshing with each other as by means of sector teeth 55-5ii. Both roll-back elements 5354 may be journalled in the case i8, and the member 53 may be provided with a spindle-engaging opening W to receive say the spindle 16 or the spindle 3 of the combinations of Figs. 1 and 2, respectively. The roll-back element 54 may include another set of sector teeth 58 to.

engage rack means, in the form of spaced openings 59 in one of the side members 49 of they meters;

proportioning willabe appreciated as: efiecting relatively large; latchecarriage displacements for giyen. angularactuation of roll-back element 53.. The fully withdrawn latch-bolt 391s shown inaFig. 4.

In 1 accordance with afeature of: the: invention; the. roll-back e1ements.-53-5t are formed. with mutually-cooperating contours to assure only a particular partial rotation. of each element 53-54 with respect to theother. In? the withdrawn: case of Fig. 4,. it will be noted.- that the limiting withdrawn: position is determined 'by abutment of an arcuate edge 60. (of reduced radius) on the roll-back element 53' with the dished. edge 6| on the roll back element. 54,, Attempts to produce further withdrawal of the: latch bolt 39, as by rotation. of the. roll-back mechanism, will. necessarily result in. abutmentof the two edges 69-6l so as: to preyenttover tressing of the rackeand-p niiln enga em 0 teeth 58 and openings 5.9,. In the. other ex t treme position, that is, with the latch bolt" 39- extended, a furtherarcuateedge 63 on: the roll.- backv element. 53 may cooperate with a suitably dished edge 64 on the roll-back element 5.4,. anda projection or shoulder F9 on element 53 may lockingly abut element 54'. Again; attempts to overdrive the roll-back. element 53' in a latch-- extending direction will result only in more re.- sistive abutment ofthe shoulder 79, and it will thus be clear that engagement of the meshing teeth 55-56- may be assured at all times, for rolls-back actuation. of the latch bolt 39.

It. will be noted that in order forcibly to extend the latchbolt 39, should the resilient'means 5.9. for such extension fail, the arcuate extent. of the sector of teeth 58 might not be suflicient: to cause thenecessary forcible-expulsion of. the latch carriage, for it will be noted that in the Fig. 3 relationship of parts, the last of teeth 58 substantially clears the rack apertures 59'. In order toprovide a means for positively-expelling. the carriage, a lost-motion mechanism in the form of a. third rolL-bacl: element. 65' may be: secured on an axis common with. the second roll-back element 54. The roll-back element 65 may be in the form of a bellcrank, having a first armor projection 66 to engage saythe back end of the carriage side plate as and a second arm or projection 61 to engage an". up-- turned. lug 63 formed on the second roll-back element 54'. If desired, the second and third: roll-back. elements: lids-65 may be: mounted on: a. pin. or stud 69, as by upsetting one end of the: pin 69 outside the frame or case plate tfl'randi by pinning the. third. roll-back element 65 to: stud 65,. as at; 70.

For-assuring positive engagernent of -the sectorx teeth 58 with the rack openings 58;. as when the. roll back mechanism is. actuated from the positions of Fig. 3 to the positions of. Fig. 4,. a slightly inwardly extending projection 'H' may be formed at the edge of the rearmost rack opening 58 so that the first sector tooth" 58 may unquestionably engage-the first rack opening 59. ment of Figs. 3, 4, and 5, a coil spring 12 may be supported by thefirst roll-back element 53, one end of spring 12 being looped around a radial'projection l3- onroll-bacls element 53 (as as 14) and the other end of the spring libeing: stressed. against the secondor. third roll-back The cooperative functioning-oi". theuabovea described par-ts; :ci 'myflatcln mechanism. willi-v For the resiliently-urged-latch1embodi-- o perhapsbezbettersunderstood fromial description of a cycle of operation, commencing; with the fully extendedpositiomof Fig. 3; In this fully extended position; the second-roll-back element 54: out of engagement with; the rack '0n;.-the" latch; carriage, except insoiarasthe thirdrolh backelementsfii may be: urged: against the; backend-of: the-carriage. Thus, the secondandthirdroll-back elements 54-455 are in engagement" at 5T-68Z Should the first roll-back element. 53 be: urged in. a. direction. for further: expulsion of thedatch" bolt 39,: thisnmotion will*be--resist'ed; by abutment of shoulder 1-9: soas: not to damage; the pro ection parts 65-61 of the third roll back element 65 Also, it willibe'noted thatathe abutment 1 of proj ection: 63 with: the carriage. is: not overstressed, due to protection; afforded by: shoulder 19. Under" the action. of spring: 12" it will be clear that: the parts are t'normallyvurged into this fully extended position.

First rotation ofroll-back elemental; :Will cause a meshing of the gear teeth 55--5"$ so asa'to' im part rotary motion to the second roll-backt-ele ment 54,- thus relieving the abutmentof projection 6'! with lug 68 and causing'-rack and-sector engagement, once theiirst'sector' tooth 5-8 abuts projection H to engage the rack openings 59. The carriageand thereforethe" latch bolt 39 may then" begin to retract.- Full retraction 1iSa CCOm-e' plished when the abutment edges Bil-bl of "meme bers' lit-54 engage, as for theiposition shown-in: Fig. l. Attempts to overstressthis" position, that is, toefiect more than necessary retraction. of thelatch bolt 39 (by roll-back actuation) may only result" in more firm binding of these abutment edges Eli-45!, so thatthere needibenopverstress ing'ofthe sector and racia- 5859 For the return stroke, inthe form-showrnthe action of spring 12' is such as to urge roll-back element 53 counterclockwise until. limited by abutment of shoulder 79. On this return stroke it will be understood that the projection 66' of the third roll-back element 65 merely rides or: slides along thesmooth inner surface of carriage member 49 until justprior to engagement-of the projection 6-7 with the lug 68", at which time the roll-back parts may havetherelationship shown in Fig. 6. This engagement preferably'occurs as the last sector tooth 58 is leaving: its engagement" with the rack 59', so that the last driven ro'tation of the second roll-back elementSA may be eiTective to force expelling displacement of the latch carriagei As indicated generally above, the above-described latch structure may also be applied" to perform the functionot a-deadbolt'. Intl're lat ter event, and referring to Figs; 9- and 10,1 pie-- fer to employ resilient means to' impart: a; snap" action for resiliently retainingthe roll-backelement 53 in one of two selected positions; In'the form shown, a spring ii; is retainedby' the emli cap 42 and serves to displace awas'her'l-l against: the pro ect-ion l3- oi' the roll-back element 5 3?; the projection 13* may-besaidto be" on oneside of thethrust axis of'spring 'lfi for one'position of? the-roll -back'means, and on the other sideof'the? thrust axis of spring for anotherposition of: the roll-back means. To provide better'engag'e ment=between the'washeror-plate' Tl andithe proj action 1-3, the proieotion T3 may be formed: with" an upturnedlug iii; When myflatchtunit is usedias;

a deadbolt, the spring 12 of Fig. 3 may bere move'd, as -it'willibe clear thatnormal resilientyex pulsionof the latch. mechanismxis not called tibia It" willlber understood that a tire iiideadsbcltipoi in Fig. 10. In the second (latter) position it will be understood that the latch bolt 39 is fully retracted. It will be seen that for the position shown in Fig. 10, the spring 7 may adequately assure that the latch mechanism will be held fully retracted.

As a further feature of the invention, it will be noted that the edge 83 of roll-back element 53 may be formed with a slightly greater arcuate extent than the edge 68 with which it is intended to mate. The edge 63 also preferably terminates in an abutment such as the radial shoulder 19. Thus, regardless of the adaptations of my latch mechanism, whether as a dead bolt or as a resilient latch, the roll-back element 53 may be resiliently urgedv (for the expelled bolt position) into abutment with the roll-back element 54 by engagement of the shoulder 19 against the latter. Because of the preferably greater arcuate extent of edge 63 as'compared with edge 64, there may be a slight angular lost motion between roll-back elements, so that under the action of either of springs l'2l6 a normal position of teeth 5555 will be as shown in Fig. 9. In this normal position (i. e. for an extended bolt) any attempt to force a retraction of the carriage (as when shank 4B is locked to the latch carriage by a strike-plate operated anti-picking device, described below) will result in an interference or bind between teeth 555S so as to prevent such forcible retraction. Thus, the only way in which the latch carriage may be retracted is by rotary actuation of the roll-back element 53.

In addition to the above mechanisms, I provide, as a feature of the invention, a novel pickor tamper-resisting arrangement which may be incorporated in the latch mechanism of Figs. 3, 4, and 5. In the form shown, an auxiliary latch 89 and an auxiliary-latch lever or dog 81 cooperate to render the latch pick-proof. The auxiliary latch 89 includes a forwardly projecting part slidably guided in a groove 52 in the latch bolt 39, and a shoulder 83 (see Fig. 5) on the auxiliary latch SB may engage the inner or back side of latch bolt 39 in order to retain the auxiliary latch 89 against extension beyond the latch bolt 39. The tail end or shank 84 of the auxiliary latch 3?! may be slidably guided in a hole in the forward end of the latch carriage, and a spring 85 between said end and a shoulder 85' on the auxiliary latch 80 may serve to urge the auxiliary latch into an outwardly extended position. The auxiliarylatch lever 8| may be generally crescent-shaped and pivotally supported as by a pin 8-6 away from the axis of shank 58. A lug 81, bent inwardly from the side plate 49, may serve to guide and position the lever 81. The free end of lever 8| may be urged by a spring 83 to ride constantly on the rearwardly projecting end of the auxiliarylatch shank 85.

As long as the door 32 is open, the latch bolt 39 and the auxiliary latch 80 may be fully extended, or they may be retracted, as by opera tion of key I5 or knob l3; in other words latch members 39 and 80 will move in unison as if they were one and the same piece. However,

upon closing the'door 32, the auxiliary latch 80 may be held retracted by the strike plate while the latch bolt 39 is projected under the influence of spring 50. With the auxiliary latch thus held in retracted position, it will be noted that a recessed portion 89 of the shank 84 thereof will have presented itself to the free end of the auxiliary-latch lever 8| so as to permit lever 8| to rotate (clockwise, in the sense of Fig. 11) and doggingly to engage a transverse slot in the shank 46. The dotted outlines of Fig. 11 indicate the position of lever 8| in the dogging position, and it will be clear that as long as lever 8| remains so disposed (i. e. as long as the door remains closed), the latch bolt cannot be picked or retractively pushed, and the door 32 may remain securely locked.

On the other hand, the door 32 may be readily opened upon actuation of the key [5 or of the knob l3 to withdraw the latch carriage, Withdrawal of the latch carriage will be understood to produce such relative motion of shanks 48 and 84 that the lever 8! will be forced (as by a camming slope at the inner end of the recess 89) to ride out of the recess 89 and therefore out of dogging relation with the shank 46 of the latch bolt 39.

It will be appreciated that I have described a novel latch-and-rosette combination, the features of which will be found particularly pract cal in application of the combination to relatively thin doors or where flush-type mountings are desired. The rosette construction is characterized by simplicity and by the fact that itmay impart additional functions to the latch With which it is combined. It will also be understood that my latch mechanism is of such simplicity as to be adaptable to manufacture substantially wholly from sheet metal, and that such a latch mechanism may be rugged and highly resistive to tampering.

While I have described my invention in detail for the preferred forms shown, it will be understood that modifications may be made within the scope of the invention as defined in'the appended claims.

I claim:

1. As an article of manufacture, a unit-handlmg rosette assembly to be mounted on one side of a door and for use in combination with a separate latch assembly and in combination with a separate latch-actuating assembly accessible on the other side of the door, said rosette comprising an inner housing plate, an outer housmg plate, a first rotatable member journalled in said inner hOllSiIlg plate and including means to be connected in latch-actuating relation with said latch assembly, and a second rotatable member geared to said first rotatable member and journalled in said inner housing plate, said second rotatable member including means to be connected in actuable relation with said latch-actuating assembly.

2 An article of manufacture according to claim 1, in which said first and second rotatable members have spindle-receiving sockets for spindle-connection to said latch assembly and to said latch-actuating assembly, respectively.

3 An article of manufacture according to claim 1, in which said rosette assembly further includes clogging means for dogging one of said members.

4. In a latch device of the character indicated a latch case, a latch slidable in said case at one end thereof, a latch carriage for said latch, and

roll-back means for said carriage, said roll-back sesame means -including :a rotatable drive member and .a rotatable driven member geared to each other,

said-driven member including a radial projection engageable with said carriage for one portion of the total movement of said drivenmember, and a further-radialprojection carried with lost-motion-by said driven member for engagement with said carriage,-said driven member bein in driving "relation with said carriage via said "further radial projection while said first radial projection is not in engagement with said carriage.

5. A-deviceaccordingto claim 4, in which the pitch diameter of the gear for said drive member is'grea-ter than the pitch diameter of the gear for said driven member, whereby a given rotation of ;said-drive member may efiect arelatively great movement of said carriage.

"6Q As'an article of manufacture, a unit-"handling rosette assemblyfor use in combination withaunit handling latch assembly, said rosette assembly comprisingan inner housin plate-an outer 'iiousing plate, a knob and a pinion member unitari ly journalled in said outer housing plate, a latch-actuating member journalled in said inner housing plate and including means to be connected to said 1atch assembly and in latch-actuating relation therewith, said latchactuating member including tooth-engaging means meshing with said pinion, and dog means radially engageable with one of said members and including dog-actuating means projecting externally of said outerhousing plate.

"7.In combination, 'a door, 'a unit-handling cylindrica1 latch assembly in an edge of said door and between the inner and outer sides of saiddoor,,acylinderlock accessible on one side of said door and including a body extending toward the otherside of the door, ,said body being radially offset from said latch assembly, and a rosette assembly on'the other side of the door and -,includin interconnected gears separately coupled toisaid cylinder lock-.and. to said latch.

In;comb ination, a unit-:handling cylindrical latch assembly comprising latch means and latch-actuatingmeans, a ,unitehandling rosette assembly comprising two geared rotatable members onispaced axes, the spacing between said axes exceeding ..the.outer radius .of said latch assembly, and .a..driving-connection including a spindle; between one. oflsaid geared members 7 and said latch-actuating means of said latch means.

9. In combination, a lock unit for access from. one side of a door and including an actuation axis, a rosette unit on the other side of the door, and a latch unit including an actuation axis, said units being separate complete assemblies, said rosette unit including two geared rotatable members on spaced axes, a spindle between one of said rotatable members and said lock, and a spindle between the other of said rotatable members and said latch, the spacing between said rosette axes being at least the distance from said first-mentioned actuation axis to the side of said lock unit nearest said latch unit plus the distance from said second-mentioned actuation axis to the side of said latch unit nearest said lock unit.

10. The combination according to claim 9, including dogging means accessible from the other side of the door and comprising a member carried by said rosette unit and engageable with one of said two geared members.

11. In combination, a door having a latchreceiving bore in an edge thereof and a transversely extending lock-receiving bore offset 'irom said first-mentionedbore, a ,unitrhandling cylindrical l-atch -in said first bore, a unit-handling cylinder lock in'saidse'cond bore and flushwith one side of said door, saidlock overlapping said latch atleastin aplane normal t the axis of said lockand including the axis of said latch, and a. unitehandli-ngrosette' including .two meshinggears adjacent the :other side of said door, and separate spindles, separately coupling said gears to said. latchand to said lock.

12. In-.combination a unit-handling latch unit having a caser-oi' generally cylindrical shape to beinsertedin a bore, said latch unit comprising a latch-and a latch-actuatingmember having axtransversely extending spindle-receiving open:- ing, a. unit=handling rosette unit comprisingtwo geared rotatable members in a housing to be mounted on theface ofa door, and a spindle in said opening and connectedtoone of said geared members, the :axes rOf said -.rotatable members beingspaced on amount exceedingthe distance betweenathe axis of said spindle-receiving opening and an outer part f said generally cylindrical latch, case, whereby a latch-actuating spindle may passthrough the. door in clearance relation with said case, for actuation of said latch via said rosette.

13. in a ,latch device of vthe character indicated, a, latch case, a latch slidable. at one end of saidcase, a latch carriage for said latch, .and roll-back means for saidcarriage, .said .rollrback means including a first. rotatable member and a .secondrotatable. member journalled on spaced axes-in,saidcaseand geared ;to each other, rack means cooperating between saidsecond member andfisaid.,.carriage for propelling said carriage, and a third rotatable Vmember carried .by and engageable -.-with .saidsecond rotatable member and having a radial projection for engagement with said ,carriage,:;there being lostmotion be.- tween saidsecondand third rotatable members, so v:that said third rotatable member may be driven-.byisaidsecond rotatable member. only for a, fraction of ;the total rotation permitted said second rotatable member.

:14. A device according ,:-tos-cl aim 13, in which said.-:r.oll-back.=means:includes resilient meansior resiliently ;urging.,one.of=said members in one direction ofyrotationqandiothe .full extent of possible movement of, said ..-one member in said one-direction.

15. In combination, a generally cylindrical latch case, a latch slidable in an end of said case, a latch carriage slidable in said case and connected to said latch, roll-back means including a first rotary roll-back element geared to a second rotary roll-back element, said latch carriage including back means meshing with one of said roll-back elements, and a rosette including a first gear coupled to the other of said rollback elements and a second gear in coupled relation with said first gear and connected to a knob, the axis of said second gear being radially offset from said latch case.

16. In a latch device of the character indicated, a latch case, a main latch slidable at one end of said case, an auxiliary latch slidable at said end of said case and positioned to be held in a retracted position by a strike plate when said main latch extends into the strike plate, latch-actuating means including a latch carriage for said main latch and slidable with respect thereto, roll-back means for said carriage, said latch-actuating means including means jamming said carriage against retraction except by operation of said roll-back means, cam means carried by said auxiliary latch, and dogging means carried with said latch carriage and positioned to be cammed by said cam means and including a part to dog said main latch when said main latch is extended, said cam means being effective to permit said dogging means to dog said main latch only when said auxiliary latch is in a retracted position.

1'7. In a latch device of the character indicated, a latch case, a main latch slidable at one end of said case and including a shank, a latchactuating carriage for said main latch and slidably receiving said shank, said shank including an abutment to be engaged for dogging purposes, a dogging lever pivotally supported by said carriage and resiliently urged in a direction to dog said shank to said carriage, slidable auxiliarylatch means including cam means operative to withdraw said lever from said dogging engagement upon a retracting displacement of said latch carriage relatively to said auxiliary latch means,

and roll-back means for said carriage, said rollback means including means normally urged to jam said carriage against retraction except upon an operation of said roll-back means.

18. A latch device according to claim 17, in which said roll-back means includes two gears which may mesh with each other to retract said carriage, said gears having for substantially one relative position thereof an effective lost-motion of meshing engagement, whereby one gear may be caused to drive the other for roll-back actuated retraction of said main latch, and whereby the other gear may jam and may therefore not be caused to drive the one, thereby preventing latch-driven retraction of said carriage.

19. In a latch device of the character indicated, a latch case, a latch slidable atone end of said case, a latch carriage for said latch, roll-back means for said carriage, said roll-back means including a first rotatable member and a second rotatable member journaled on spaced axes in said case and geared to each other, rack means cooperating between said second member and said carriage for propelling said carriage, a third rotatable member freely pivoted on a common axis with said second member and having a radial projection for engagement with said carriage, and abutment means cooperating between said second and third rotatable members for imparting a positive rotary drive to said projection for one direction of rotation of said second member.

20. In a device of the character indicated, a latch case, a latch slidable in said case, a latch carriage connected to said latch and slidable in said case, and roll-back means engageable with said carriage for actuating said latch, said rollback means including a rack on said carriage, driven gear means journaled in said case and engageable with said rack, drive gear means in driving relation with said driven gear means, a cap over the back end of said case, a radial projection on the one of said gear means which is nearer said back end, and spring means retained by said cap and compressionally urged against said projection, said projection being on one side of the thrust axis of said spring means for one position of said roll-back means, and on the other side of the thrust axis of said spring means for another position of said roll-back means.

21. In a latch device of the character indicated, a latch case, a main latch slidable at one end of said case, an auxiliary latch slidable at said end of said case and positioned to be held in a retracted position by a strike plate when said main latch extends into the strike plate; latchactuating means including a carriage and rollback means therefor, said carriage being movable only upon actuation by said roll-back means, cam means carried by said auxiliary latch, and dogging means carried with said latch carriage and positioned t be cammed by said cam means and including a part to dog said main latch when said main latch is extended, said cam means being effective to permit said dogging means to dog said main latch only when said auxiliary latch is in a retracted position.

FRANK MCCONNELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,876,080 Schlage Sept. 6, 1932 2,044,622 Michauka June16, 1936 2,046,790 Phillips July 7, 1936 FOREIGN PATENTS Number Country Date 482,819 France Feb. 5, 1917 658,262 France June 3, 1929 691,499 France Oct. 22, 1930 

